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@uiten gisten strat (titre VJOHN B. MIGNAULT, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO HIMSELF AND ALFRED B. HALL, OF SAME PLAGE.

Letters Patent No.'73,824, dated January 28, 1868.

IMPROVED PILE-.CUTTING MACHINE.

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TO` ALL WHOM IT MAY CONCERN:

Be it known that I, JOHN'B. MIGNAULT, of Boston, in the county of Sutolk, and State otl Massachusetts, have invented certain Improvements in Machines for Cutting Files, of which tho following is a full, clear, and exact description, reference being had tothe accompanying drawings, makingpart of this specification, in Which*- Figure 1 is a perspective view of the front of a file-cutting machine with my improvements applied thereto.

Figure'Z is a rear elevation of the same. A l

`Figure 3, a vertical section on the line fc :vof iig. 2.

. Figure 4, a vertical section on the line y y of g. 2.

Figure 5, a vertical section on the line z z ot the saine figure; and Figure 6, a detail representing the cutter, with its spring-arm, and some of the mechanism for operating the same. I' i The process of cuttingflles by machinery, as heretofore constructed, has been attended with very unsatis factory results, e., it has been found impracticable to make every tooth of thcsam'e uniform height, and with as smooth' an edge as' can be produced by hand. Some of the difficulties to be overcome in order to obtain the desired result may be enumerated as follows, viz

First. vThedensity of the steel or metal of which the blank isoomposed is apt to vary at diffe-rent points through its length, and where the cutter or chisel was rigid, and operated by uniform blows of a hammer, it was impossible to raise the roughened surface to a uniform level, as the indentations uponl the soft places were much deeper than those upon the hard'places, vand a corresponding irregularity of tooth was the result.

Second. The blank is frequently wider from the tang tothe eentr'e than at its opposite end, and it is obvious that a given force, that will make` the required indenture at vthe wider part of the` tile, will drive the cutter or chisel,too deep at the narrower part or point of thesile. I

Third. The tile-blank frequently tapers in thickness, as well as in width, and a further allowance or adjustment is required to prevent the hammer` from falling through a greater distance when operating upon the thin than on the thick part of theblank.

Fourth. The workman, when cutting tiles by hand, adjusts his cutter, preparatory to each cut, by drawing it back against the burr or front of vthe tooth last out, the straps he employs enabling him to perform the said foiice. With machinery, however, it is different, for while it is necessary that the'iile have a. comparatively soft bed on which to rest for the protection of the teeth on one side, while the other side is being cut, it is equally necessary that this bed be unyielding, otherwise the action of the hammer and chisel upon its surface will vary at different points; and, in oonnectioniwith the above requirements, there is another still more important, that, the blank be held iirmly and immovably upon its bed in order to properly receive the blgw imparted by the hammer to the cutter, and to be accurately fed between the successive cuts. l v

My invention has for its object to overcome (as far as possible) the above-mentioned difficulties, and consists lchieiy in pivoting the cutteil or chisel loosely to a spring-arm, the cutter being so pressed by a spring as to throw its outer edge down upon the blank, while its inner edge is slightly raised above it, to be subsequently brought down by the elongation or increased leverage of the spring-,arm resulting from its retracting power, whereby the chisel is made to adjust itself to theconformation of the surface of the blank before being struck by the hammer, the springerm enabling the chisel to yield while being struck, thus causing it to move in a manner similar to that when the operation oi' cutting is performed by hand.

My invention also consists in sliding the block to which the springarm carrying the cutter is attached within a slot in the framework, to allow of the various adjustment-s of the cutter necessary for producing any required inclination of out; and myvinvention also consists in an adjustable sliding lever, provided with n screw for lifting ythe sprngarm to raise the chisel from oit the blank while being fed forward: l

To enable others skilled in the art to'underst'and and use my invention, I will proceed to describe the manner in which l have carried it outA i l 1 o In the said drawings, A is the bed, from which rise standards B in suitable bearings; inwhich'revolves the shaft C, which is driven by power applied tothe pulley D, a vloose pulley, E, being provided for disconnecting the machinery from the power, when desired. The .shaft C carries two cams, F G, (to be described hereafter,) and at one of its extremities a bevel-gear, H, which engages'with aA corresponding gear,'I, on a short shaft, J, which turns in bearings K, the inner c nds of which are screwed, at a, to the upper side of one of the standards B. One .end of the shaft J projects Aoutside one of its bearings, and carries a circular disk, L, having a dove-tailed groove, b, extending diametrically across it for the receptionof a block, M, of corresponding form, to slide therein. To a stud projecting from this block M is secured one end of a long arm or connecting-rod,

'N, the other end of which is attached b y a pin,'c, to a crank, O, on one end of a horizontal screw-shaft, P, which has its bearings in the bed A, and passes through a projection on the under side of atable, Q,'(sec iig. 5.) Upon a raised portion of the bed A are formed dove-tailed ways d, upon which the under side of the table fits, the revolution of the screw-shaft causing ituto slide back and forth thereon.

To the upper side of the table Q is' secured, at e, a shield, R, the upper surface of which is made of soft metal to serve as a rest for the {ile-blank S, and to protect the teeth on one side from injury when the blank is turned over to form the teeth on its opposite side. The tang of the blank passes through an aperture in a block, f, which tits and moves vertically in a'square slot cut in the shield, the lower end of the block being enlarged to prevent its removal from the upper side, the end of the tang resting in a cavity formed in a metal piece, g, screwed to the shield R, by which means (in connection with a wedge-shaped key, h, passing through the block f) the blank, when pressed down by the binder'l, (presently to be described,) is prevented from moving laterally, while it is free to rise and fall slightly in a vertical direction to allow its lower surface, vwhile being cut to rest snugly upon and {it the shield at the point immediately under the hummer and chisel, to properly receive the blow withoutbeing bent.

Secured to the table Q is a former, U, the shape of the upper surface of which corresponds exactly to that of the upper and lower sides of the blank to be cut. Upon this former rests a roll, e', which isfree to revolve thereon when the table is moved back and forth, the roll turning up'on a pin, j, which passes through the bifur cated ends of an arm, r, which ,is secured by a pin, Z, immovably to a shaft, m, which rests in bearings in the side of the standards B. u

"rt is a stili' spring, of the form shown in gs. 1 and 3, one end of which is screwed to.a square projection, o, formed on the shaft m, the other end passing near to and directly under the heel or projection p, formed on the helve of the hammer V,landbeing provided with a hole, into which turns a screw-bolt, q, for the purpose of regulating the tension of the springand consequentlyv the vibrations of the hammer, when operated by the revolution ofthe cam F. v

rt is a checlrf'nut for retaining the spring in place after being adjusted. The hammer-belve is securely xed to a shaft, s, which is pivoted on 4the conical ends of -two spindles t, which are provided with screw-threads to* allow the shaft s to move to oneside or the other when the hammer requires to be adjusted over the chisel or cutter, the construction of which will new be explained.

pona pin, u, passing through an ope-ning at one end of a spring-arm, W, is loosely pivoted a cutter, X, of the form seen, one side of the head of which, from 10 to 11, is made slightly rounding, and receives the blow of the hammer, the other side of its head being curved downward to the point 12, (see lig. 6.) Owing tothe inclination of the cutter from the vertical, 'and that of its edge across the length of theblank, necessitated by the changes inthe position of the spring-arm, the head of the cutter is made to one side of the centre, inorder to insure the blow of the hammer being imparted directly to the centre ofthe blank'. The inclination of the cutter with respect to the blank (horizontally and vertically) is the' same as when the operation is performed by hand iii order to throw up teeth of the required form. v

Y is a bent spring for throwing the outer edge of the cutter down upon the blank, and at the same time lifting its inner edgerslightly up therefrom, the pressure or retraction of the spring-armv downward serving subsequently to push the outer edge of the cutter along the blank, and bring the inner edge of the cutter down thereon, by which means the whole length of the cutter-edge is made to snugly embrace the blank in thedirec tion required to be given the cut. '.lhe spring Y also prevents the cutter from vibrating too far; otherwise it would be liable to be struck before it had time to adjust itself to the face of the blank. l

The tension or resistance of the spring-arm serves to keep the cutter X constantly pressed down upon the blank until relieved periodically by mechanism (soon to be described) to allow of' the-feeding of the blank. The end of the spring-arm W, opposite to that in which the cutter is pivoted, is screwed, at13, to a square metal block, Z, tlelower endofwhichts into and slides within a curved slot,14, cut in the bed A, and when adjusted into the required `position for making the cut desired, is securely held in place by tightening the scre\v-nut 15.

On ,the end of the shaft m opposite to that to which the former is secured, is loosely fitted a sleeve, v, terminating in a' bent arm, w, to the` portion 16 of which is 'secured a circular leeve or roller, which .is confined thereon by a washer and pin, (not showrn) and serves as a binder, T, to press the blank (while being fed forward) down firmly on its shield at a point immediately in advance ofl the cutter. y

The device employed for holding the binder down uponl the blank while being'cut,.and for releasing it from the `shield to remove 'or turn it over, will now be described. I

2O is a bent spring, one end of which is secured, at 21, to the upper side of the sleeve 11, the other end of the spring resting upon a cam or eccentric, 22, which is pivoted, at 23, to one ofthe standards B, and is operated by hand by means of its arm or lever 24. f A'.lloapost or standard; 25, 'rising from the bed A, is pivoted, at 26, a bent lever, 27, of theform shown in section, g. 4, thel'upper end of which rests against the cam G, by which it is operated. v'.lo the lower end of this lever 27 is secured, by means of a screw-bolt, 28, an arm, 29, provided with a slot, 30,'through which the bolt 28 passes..4 One end of this arm, is provided with a screw, 31,whi`ch may be turned therein up against the under side ofthe spring-arm W, to throw the cutter up from oli` the blank after the stroke of rthe hammer, (see fig. 4.)

By the construction above described, the length of'the leverage ot' this arm may be increased or diminished to bringthe screw 31 under and support it at all times during the various positions occupied by the block Z within its slot 14.

The number of teeth, and the space between them, are regulated by the following mechanism: 32 is a toothed Wheel or ratchet secured to the horizontal screw-shaft P, and is turned by the vibration ot' the crank O, which .l also operates a .retaining-pawl, 33, which is prevented from being thrown up out of contact with the wheel by means of a coiled spring, 84, the length of the throw of the connecting-rod N being increased or diminished by sliding its block M farther from or toward the centre of the disk L, Vthus causing the pawl to drop into o. greater or less number of teeth, according as the file is to be oo arser or'tiner.

35 isa stit bent spring carrying a rubber 'block or cushion, 36, to prevent the hammer from recoiling too far to strike the cutter the second time to form one tooth.

Operation.

The blank being fitted toits shield, and its tang wedged in place wlthinthe blockf, the table is moved until the point 37 of the blank is' brought under the cutter, which, in making the'irst or over cut, occupies (with its arm and block) the positionsshown in red, tig. 1, the cutter being so plu-ced that the upper portion, ,10 to 11, 0f its head is reversed, that is, it is removed farther from the axis of the sliding bloekZ than shown in section, fig. 6, this being the only position in which the cutter will impart the blow directly to the centre of the blank. l

The slotted arm 29 is now slid in till its screw 31 is brought under the spring-arm W and turned up against it, so that it may raise the cutter while the blank is feeding. i

After the tension of the hammer-spring n is regulated, and the adjustments of. the connecting-rod N made to conform to the neness of le required, the binder T is pressed down upon the blank, (rolling over its upper surface immediately in advance of the cutter,) and the power is applied to the driving-shaft.

The motion of the table A causes the former U to travel under the guide-roll z', which is thus raised and lowered, thereby increasing or diminishing the resistance of the spring n, and consequently regulating the force of the hammer and depth ofthe tooth made by the cutter to those portions ofthe blank corresponding in shape to those of the-former" U. The cutter being loosely pivoted, its edge is free to swing or rock upon the blank till it snugly and fairly rests upon its surface, when the hammer is raised by the cam F pressing on its heel or projection, io, after which the cam is liberated therefrom, and the resistance of the spring n throws it down upon the head of the cutter.

As the shaft continues to revolve, the cam G strikes the upper end of the bent lever 27, pressing it outward, and at the same time throwing up the slotted arm 29,- and causing the screw 31 to lift the spring-arm W to raise thefcutter X from off the blank, which is now fed forward, the binder T rolling freelylover its upper surface and holding the portion of the blank under the cutter rmly upon its shield while being struck, thc bloekf allowing the blank to adapt'itself snugly and truly thereto.

After the blank is fed, (when one tooth has been cut,) the end of the slotted'arm 29 is depressed by the action of the cam G onthe upper-end ofthe bent lever 27, and the screw 31 is carried dowmbelow the spring arm W, the resista-nee of which, on being liberated, causes the cutter X again to adapt itself to the blank, in a manner previously explained.

AAfter one row of teeth has been cut, the power is, disconnected by throwing the belt upon the loose pulley l E, and the table'is turned back by revolving the'screw-shaft P into its original position. The block Z is now slid in its slot 14 to the position seen in black, 'g. 1, and the cutter being reversed in its spring-arm W, the blank isvready to receive the second or cross-cut. After the two rows of teeth have been out on one side ofthe blank, and the feed of the table is discontinued, by lifting the pawl 83 out of contact with the ratchet 32, the wedge i is driven out of the block f,-and the blank removed and turned over, to be again secured therein to receive similar cross-rows of teeth on its other side. A l v It is evident that the shape and position of the spring Y,.as well as the material of which it ismade, may be changed; for instance, it may be a spiral or rubber spring, and be placed at the back of tho head of the cutter, and any other device for eiecting the same end may be employed insteead ofthe spring Y. The mechanism may also be so multiplied as to cut a number of tiles at one operation, wit-hout departing from the spirit of o my invention. n

It will be seen from the foregoing-description that when va cutter is employed, in connection with a spring or 4:ilexiblc arm, W, and spring, Y, the operation ol' cutting the teeth can be performed in a manner entirely satisfactory, as the motion and position of the cutter are similar to those given by hand,

What I claim as my invention, and desire to secure by Letters Patent, is d 1. I claim a cutter, X, pivoted loosely to a spring-arm, W, in combination with a spring, Y', substantially as and for the purpose set forth. l

2. I also claim the combination of the adjustable block Z, cutter X, and bed R, substantially as and for the purpose set forth. i

3. I also claim the lever 27, with its slotted arm 29,in coiubination with the adjustable screw 31, or its equivalent, substantially as and for the purpose described. l

JOHN B. MIGNAULT.

Witnesses:

N.. W. SrsAnNs, P. E Tssonsmxnn. 

